<td>{{category.id | count}}</td>

/**
* @Access(admin=true)
* @Route(methods="POST")
* @Request({"id": "integer"}, csrf=true)
*/
public function countAction($id){
 return ['status'  => 'yes'];
}

filters: {
 count: function(data){
  var count = '';
  this.$http.post('/admin/api/dpnblog/category/count' , {id:data} , function(success){
    count = success.status;
  }).catch(function(error){
    console.log('error')
  })
  return count;
 }
}